Paving stones, especially for the construction of roads, are often realized as coupling systems on account of the security against displacement. These coupling systems are based on the principle that coupling members on one stone flank in the basic grid engage into the spaces of the coupling members disposed in the basic grid on the flank of the adjacent stone and prevent displacement of the stones with respect to one another in cooperation with the filling of the joints. In common use is the so-called “revolving system” according to which the coupling members are disposed on all side flanks of the paving stone diametrically and engage into one another in a predetermined basic grid on all sides independently of the position of the stones with respect to one another. According to this system the stones have a defined upper face and lower face. When laying the paving stones it is critical that the stones have no contact with one another, if possible, and are rather separated from one another by joint material. By this it is guaranteed that no damage to the pavement structure on account of temperature variations and material expansions in connection therewith can occur. However, in practice one can frequently observe that the laying is done stone by stone since this is faster and more economical for the first view.
For avoiding this disadvantage it is known from EP 1 036 882 to provide artificial stones for paving purposes with coupling portions having spacers that set a minimum distance between the stones/coupling members. The area for contacting an adjacent stone is so small that it secures the ideal position of the stone with the desired joint spacing during laying, however, is at least partly destroyed during jarring of the laid pavement. It is a disadvantage of the pre-known systems that they cannot be applied to stones with larger dimensional tolerances (for instance to clinker bricks made of baked clay). The reason for this is that the coupling members no longer engage into one another with larger dimensional differences of the stones. Accordingly, the interengagement necessary for coupling is not obtained. If the spacing between the coupling members is selected so large that the necessary tolerance with different size stones is given this results in an excessive laying clearance which results in laying mistakes in practice. The sum of smaller dimensional tolerance errors throughout several stones results in leaving the coupling grid which can result in a degradation or even in a loss of the necessary coupling effect.